Truncus Arteriosis - PEDS ???

[wynkky]

Can someone explain why there is bounding pulses on truncus arteriosis?

Thank you very much

[Esme12, ASN, BSN, RN]

Think about the pathophysiology of this disorder. Would this disorder make the heart work harder? How is the blood flow affected? Children increase the cardiac output not by more forceful contractions but faster contractions of the heart.

Truncus Arteriosus

http://www.ceufast.com/courses/viewcourse.asp?id=65

Truncus Arteriosus

Truncus arteriosus (TA) is an uncommon congenital cardiovascular anomaly that is characterized by a single arterial trunk arising from the normally formed ventricles by means of a single semilunar valve (ie, truncal valve). In addition, the pulmonary arteries originate from the common arterial trunk distal to the coronary arteries and proximal to the first brachiocephalic branch of the aortic arch. The common trunk typically straddles a defect in the outlet portion of the interventricular septum (ie, conal septum); however, in rare cases, it may originate almost completely from the right or left ventricle. In patients with a patent and normal caliber aortic arch, the ductus arteriosus is either absent or diminutive.

The earliest classification, developed by Collett and Edwards in 1949, includes truncus arteriosus types I-IV, as follows:^[1]

• Truncus arteriosus type I is characterized by origin of a single pulmonary trunk from the left lateral aspect of the common trunk, with branching of the left and right pulmonary arteries from the pulmonary trunk.
  
• Truncus arteriosus type II is characterized by separate but proximate origins of the left and right pulmonary arterial branches from the posterolateral aspect of the common arterial trunk.
  
• In truncus arteriosus type III, the branch pulmonary arteries originate independently from the common arterial trunk or aortic arch, most often from the left and right lateral aspects of the trunk. This occasionally occurs with origin of one pulmonary artery from the underside of the aortic arch, usually from a ductus arteriosus.
  
• Type IV truncus arteriosus, originally proposed by Collett and Edwards as a form of the lesion with neither pulmonary arterial branch arising from the common trunk, is now recognized to be a form of pulmonary atresia with ventricular septal defect rather than truncus arteriosus.
  
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